047 permutations ii
47. Permutations II
题目: https://leetcode.com/problems/permutations-ii/
难度:
Medium
跟第46题一样，就是最后append的时候不一样，只有没有结果里面没有的才加入
class Solution(object):
def permuteUnique(self, nums):
"""
:type nums: List[int]
:rtype: List[List[int]]
"""
if len(nums) == 0:
return []
if len(nums) == 1:
return [nums]
res = []
for i in range(len(nums)):
prefix = nums[i]
rest = nums[:i] + nums[i+1:]
for j in self.permuteUnique(rest):
if [prefix]+j not in res:
res.append([prefix]+j)
return res
